Nepeta catariaL. (catnip) can serve as a chassis for the engineering of secondary metabolic pathways

Abstract

AbstractObjectiveEvaluation ofNepeta catariaas a host with specific endogenous metabolite background for transient expression and metabolic engineering of secondary biosynthetic sequences.ResultsThe reporter geneGFP::licBM3 as well as three biosynthetic genes leading to the formation of the cannabinoid precursor olivetolic acid were adopted to the modular cloning standard GoldenBraid, transiently expressed in two chemotypes ofN. catariaand compared toNicotiana benthamiana. To estimate the expression efficiency in both hosts, quantification of the reporter activity was carried out with a sensitive and specific lichenase assay. WhileN. benthamianaexhibited lichenase activity of 676 ± 94 μmol g-1s-1(Gerasimenko et al. 2019),N. catariacultivar ‘1000’, and the cultivar ‘Citriodora’ showed an activity of 37 ± 8 μmol g-1s-1and 18 ± 4 μmol g-1s-1, respectively. Further, combinatorial expression of genes involved in cannabinoid biosynthetic pathwayacylactivating enzyme 1(aae1),olivetol synthase(ols) andolivetolic acid cyclase(oac) inN. catariacv. resulted presumably in thein vivoproduction of olivetolic acid glycosides.ConclusionNepeta catariais amenable toAgrobacterium-mediated transient expression and could serve as a novel chassis for the engineering of secondary metabolic pathways and transient evaluation of heterologous genes.